Why the heck on widescreen TV's, do they still set the aspect ratio on them in such a way that you still get borders?

I've only watched 1 blu-ray film that actually works at full 16:9 my TV supports, without black bars on the top and bottom, and that was the original Spiderman Blu-Ray film in this set my mate bought. The other 2 in the set have borders, which made the first film appear to have a better quality image than the latest offerings.

This shouldn't happen with a widescreen TV, since its meant to be wiiiddeeee and so show right. It was fine when I had a 4:3 TV, but now I have a 16:9 I expected all films to appear full screen.

Looking at the back, ones that show 2:35:1 and 2:40:1 appear with black bars, and most HD-DVD's I've seen show at 2:35:1.

well movies that are on dvd, that are sold as widescreen format have different aspect ratios. do u only see black bars at the top and bottom or do u also see them at the side? and whats so bothersome about the bars?